In the automotive field, the use of sensors such as microphones and/or accelerometers is known for the acquisition of signals generated by a source inside the engine compartment which are then suitably processed by specific algorithms to obtain information concerning the components arranged in the engine compartment, such as for example the rotational speed of the turbocharger, the occurrence of knocking phenomena, ignition failure phenomena, the engine load, the closing of the intake and/or exhaust valves, etc.
Typically, the sensors are installed directly onto the electronic control unit of the internal combustion engine or are housed on a measuring device provided with a processing unit (a microcontroller) for the signal, which is in turn connected to the electronic control unit of the internal combustion engine.
For example, the document EP-A1-1843024 describes a method for controlling an internal combustion engine comprising an engine block containing rotatable members and a control unit that is physically separated from the engine block and provided with a number of sensors, which are arranged to detect the intensity of the pressure waves generated by the internal combustion engine. The control unit is configured to determine, depending on the intensity of the pressure waves detected by the sensors, the value of at least one operating parameter of the engine such as, for example, the speed of the rotatable members or the occurrence of knocking phenomena inside the cylinders.
A solution of the above type, however, has some disadvantages. In particular, the application of the sensor directly onto the control unit of the internal combustion engine is limiting from the positioning flexibility point of view, because of the constraints imposed by the size of the electronic control unit. In addition, these solutions have considerable costs, which are related to the signal processing electronic components, which are provided on the measuring device itself.